/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard;

import java.io.IOException;
import java.io.PrintWriter;

import proguard.classfile.ClassPool;
import proguard.classfile.visitor.AllMemberVisitor;
import proguard.classfile.visitor.ClassCleaner;
import proguard.classfile.visitor.ClassPoolVisitor;
import proguard.classfile.visitor.MultiClassVisitor;
import proguard.classfile.visitor.SimpleClassPrinter;
import proguard.optimize.KeepMarker;
import proguard.optimize.KeptClassFilter;
import proguard.optimize.KeptMemberFilter;

/**
 * This class prints out the seeds specified by keep options.
 *
 * @author Eric Lafortune
 */
public class SeedPrinter {
    private final PrintWriter printWriter;

    /**
     * Creates a new ConfigurationWriter that prints to the given writer.
     */
    public SeedPrinter(PrintWriter printWriter) throws IOException {
        this.printWriter = printWriter;
    }

    /**
     * Prints out the seeds for the classes in the given program class pool.
     * 
     * @param configuration the configuration containing the keep options.
     * @throws IOException if an IO error occurs while writing the configuration.
     */
    public void write(Configuration configuration, ClassPool programClassPool, ClassPool libraryClassPool)
        throws IOException {
        // Check if we have at least some keep commands.
        if (configuration.keep == null) {
            throw new IOException("You have to specify '-keep' options for the shrinking step.");
        }

        // Clean up any old visitor info.
        programClassPool.classesAccept(new ClassCleaner());
        libraryClassPool.classesAccept(new ClassCleaner());

        // Create a visitor for printing out the seeds. We're printing out
        // the program elements that are preserved against shrinking,
        // optimization, or obfuscation.
        KeepMarker keepMarker = new KeepMarker();
        ClassPoolVisitor classPoolvisitor = new KeepClassSpecificationVisitorFactory(true, true, true)
            .createClassPoolVisitor(configuration.keep, keepMarker, keepMarker, keepMarker, null);

        // Mark the seeds.
        programClassPool.accept(classPoolvisitor);
        libraryClassPool.accept(classPoolvisitor);

        // Print out the seeds.
        SimpleClassPrinter printer = new SimpleClassPrinter(false, printWriter);
        programClassPool.classesAcceptAlphabetically(
            new MultiClassVisitor(new KeptClassFilter(printer), new AllMemberVisitor(new KeptMemberFilter(printer))));
    }
}